Make scrollable viewport size no longer depend on clip layer.

cc/layers/scrollbar_layer.cc

 
 // Copyright 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "cc/layers/scrollbar_layer.h"
 
 #include "base/auto_reset.h"
 #include "base/basictypes.h"
 #include "base/debug/trace_event.h"
@@ skipping 119 matching lines @@
 
   if (track_ && track_->texture()->have_backing_texture())
     scrollbar_layer->set_track_resource_id(track_->texture()->resource_id());
   else
     scrollbar_layer->set_track_resource_id(0);
 
   if (thumb_ && thumb_->texture()->have_backing_texture())
     scrollbar_layer->set_thumb_resource_id(thumb_->texture()->resource_id());
   else
     scrollbar_layer->set_thumb_resource_id(0);
+
+  scrollbar_layer->set_is_overlay_scrollbar(scrollbar_->IsOverlay());
 }
 
 ScrollbarLayer* ScrollbarLayer::ToScrollbarLayer() {
   return this;
 }
 
 void ScrollbarLayer::SetLayerTreeHost(LayerTreeHost* host) {
   if (!host || host != layer_tree_host()) {
     track_updater_ = NULL;
     track_.reset();
@@ skipping 186 matching lines @@
     thumb_size = gfx::Size(scrollbar_->ThumbLength(),
                            scrollbar_->ThumbThickness());
   } else {
     thumb_size = gfx::Size(scrollbar_->ThumbThickness(),
                            scrollbar_->ThumbLength());
   }
   return ScrollbarLayerRectToContentRect(gfx::Rect(thumb_size));
 }
 
 }  // namespace cc